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Natural bovine behavior key to evaluating management practices

By Lee J. DiVita

Posted Jan. 1, 2001

Human-animal interaction is one of the largest components of appropriate animal welfare. More than anything, the natural behaviors of animals need to be examined, and only then can science answer concerns dealing with bovine welfare. The stressors that affect beef and dairy cattle and veal calves, whether environmental or social, need to be recognized. Julie Morrow-Tesch, PhD, leader of the USDA Agricultural Research Service Livestock Issues Research Unit, believes human-animal interaction is a symbiotic relationship.

Dr. Morrow-Tesch spoke on management practices involving stressful procedures, both social and physical. "Social stress includes isolation, regrouping, and crowding, all natural components of cattle production." She believes that these social stressors carry a psychologic component not often considered or understood. Wind and dust, transportation, heat and cold stress, and nutritional stresses also should be considered.

"There needs to be more research into bovine neuroendocrine responses to stress, as well as their immune responses to stress," Dr. Morrow-Tesch said. "We need to fully understand how cattle perceive their environment. Cattle have a much different visual sense than humans. Their hearing, olfactory sense, and tastes are different than humans'."

As such, producers should be aware of and change environmental factors that adversely affect cattle, such as thermal and space requirements, ventilation, and flooring. Dr. Morrow-Tesch said these environmental factors in management are easy to fix.

Reemphasizing points of AnnMaria de Grassi's opening overview, Dr. Morrow-Tesch evaluated branding, tail docking and castration. "In cattle production, we have to perform some painful procedures on the animal that are generally short term and short in duration. We do this because we're looking out for the welfare of those animals later on. We have to consider how practical it would be for a cowboy to ride into a pasture with a huge liquid nitrogen tank to perform freeze branding, a method shown to be less stressful than hot-iron branding."

The practicality of medical procedures, alternatives, and how to make changes need to be considered. Questions to be answered are: Can we use analgesics and anesthetics while performing these procedures? Are workers properly trained to use them? Are they available? Are these procedures done correctly, for the right reasons? Are we using the best methods, training and equipment?

The USDA-ARS did two studies on castration, one using surgical castration and one using the banding method. It showed that, by far, surgically castrating calves prior to weaning is the best method. The calves seem to show lower stress responses, such as reduced activity.

Tail docking of dairy cows seems to be more an issue of human comfort. "Humans do not like to be hit in the face with a manure-filled tail," Dr. Morrow-Tesch said. In North America the practice in cows is fairly new and on the rise. Reasons for tail docking include milking cleanliness, ease of attachment of milking equipment, cow cleanliness, and udder health.

Yet some research finds no difference in health and milk quality between cows with docked and undocked tails. The US dairy industry has survived many years without tail docking. Traditional ways of keeping animals clean including trimming the switch, providing adequate bedding, and frequently cleaning the barn, all the responsibility of the producer.

"Cows have tails for a reason, and that is to keep flies off the animal and to communicate to other animals," Dr. Morrow-Tesch said. "Two times as many flies are showing up on cows with docked tails than undocked tails." Research showed that, contrary to traditional wisdom, the banding method of tail docking is not painful in adult cows compared to calves. Cows with docked tails have been shown to have higher stress-hormone concentrations, while calves do more pain behavior-related stomping.

The subject of early weaning of dairy cattle is important to welfare-conscious consumers. Behavior research shows that the longer the calf is left with the cow, the tighter that social bond will be, and the more stressful it becomes on the cow and the calf when the young animal is weaned. Dr. Morrow-Tesch feels that because of this, it is reasonable to remove the dairy calf from the cow at a young age.

Social stresses that affect production are currently lacking adequate research. Because the bovine species is social, animals in groups form a dominance hierarchy. "The position the animal has in that social hierarchy has something to do with its response to stress," Dr. Morrow-Tesch said. "In feedlots we examined what we called agonistic behaviors, which meant they were butting heads, bulling, running around, fighting, and being both dominant and submissive. Basically, they were behaving to sort out the dominance hierarchy."

A simple way to reduce the number of aggressive incidents by half and reduce dust levels is to alternate feeding times, Dr. Morrow-Tesch said. By nature, cattle want to eat at sunset. Cattle will naturally find other methods of entertainment (eg, bulling) when their feed bunk is empty. "Preliminary data indicates that if feed remained in their bunk at sunset, cattle ate and then rested," she said. "Not only did their behavior change, but dust levels were also reduced."

On the basis of USDA-ARS research, Dr. Morrow-Tesch suggested paying close attention to and learning from the natural behaviors of animals, as well as addressing what consumers and producers want.

"Producers want to do the right thing," Dr. Morrow-Tesch said, "but we scientists need to help them."